Stabilizing apparatus for aeroplanes and the like



E. E. KITTREDGE. STABILIZING APPARATUS FOR AEROELANES AND THE LIKE.

APPLICATION FILED NOV. 27, I916.

Patented Mar. 23, 1920.

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E. E. KITTREDGE.

STABILIZING APPARATUS FOR AEROPLANES AND THE LIKE.

APPLICATION FILED NOV.27,191E.

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Patented Mar. 23, 1920.

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STABILIZING APPARATUS FOR AEROPLANES AND THE LIKE. APF'LICATION FILED NOV-27, I916.

. UNITE STATES PATENT OFFICE.

EVERETT E. KITTREDGE, OF MONTREAL, QUEBEC, CANADA; DAVID KITTREDGE ADMINISTRATOR OF SAID EVERETT E. KITTREDGE, DECEASED.

STABILIZING APPARATUS FOR AEROPLANES AND THE LIKE.

Specification of Letters Patent. Patented Mar. 23, 1920.

Application filed November 27, 1916. Serial No, 133,716.

To all whom may concern:

Be it known that I, EVERETT KIT- run-non, a subject of the King of Great Brit ain, and a resident of the city of Montreal, in the Province of Quebec and Dominion of Canada, have invented certain new and useful Improvements in Stabilizing Apparatus for Aeroplanes and the like, of which the following is a full, clear, and exact -description.

This invention relates to improvements in stabilizing apparatus for aeroplanes and the like, and the object of the invention is to provide a simple and reliable electro-mechanical device for controlling an aeroplane.

both automatically and at the will of the operator. r

The device consists of a driving motor for the various rudders of the machine, a magnetically operated multiple clutch connecting the motor with the rudders, and circuit makers for controlling the flow of current to the magnets. These. circuit makers, which areof the pendulum type, are mounted'in a frame which may be tilted with respect to the aeroplane for guiding the same at the will of the operator. When once the pendulum circuitmakers have come to rest in any desired position, it is obvious that tilting of the aeroplane from external influences will result in relative movement between the aeroplane and pendulum circuit makers, so that automatic regulation will be effected.

In the drawings which illustrate the invention:--

Figure 1 is a perspective diagram showing the arrangement of the various parts in their relation to onevanother.

Fig. 2 is a plan view showing the arrangement for manually controlling the circuit makers.

Fig. 3 is an elevation partly in section of the multiple clutch mechanism.

Fig. 4 is a section of one of the circuit makers on the line 44, Fig. 2.

Fig. 5 is a section of the circuit maker on the line 51-5, Fig. 4.

Fig. 6 is a wiring diagram of the device.

Referring more particularly to the drawings, 11 designates a forward rudder arranged in a horizontal plane with axis transverse to the direction of travel for controlling the elevation and depression of the aeroplane, and 12 and 13 the right and left A multiple clutch mechanism, designated as i a whole by the numeral 15, is provided in a suitable part of the aeroplane, and includes two drums or-pulley sheavesl6 and 17, the former of which is connected in any suitable manner to the forward rudder 11, as for instance by an endless belt or rope 17, and the latter of which is connected to the side rudders 12 and 13, and the stern rudder 14, by means, such as the endless belt or rope 18. Power delivered by the motor 19 is conveyed through the belt 20 or otherwise to the clutch mechanism, and from thence to the various rudders. The motor 19 may be a special motor of electric or other type, in which case the belt may be omitted and the motor directly connected to the clutch. This motor may, however, be the driving motor of the aeroplane, in which case belt connecspeed of motor driving the aeroplane, so

that the action of the guiding mechanism will be uniform at all times.

The multiple clutch is operated by electromagnets, the current flow to which is controlled by circuit closers or switches, designated as a wholeby the numerals 21 and 22. The former of these switches is located in a vertical plane parallelwith the direction of travel of the aeroplane,-and is for the purpose of controlling elevation and depression of the machine, while the latter switch is arranged in a transverse vertical plane, and controls movement in lateral directions. The switch 21 is pivotally suspended at its upper end between the arms of a yoke 23, which is revolubly connected to the casing 24, containing miter gears 25, which together with the shaft 26 connect the yoke to the hand wheel 27 located conveniently to the operator. As will be clearly seen from Figs. 1 and 2, the axis of revolution of the casing 24 is parallel with tion withthe clutch will be preferable, al-

' the longitudinal axis of the aeroplane, so

that the axis of the yoke is transverse thereto, and any revolution of the casing will direction. As, however, this switch is sensitive only to oscillations in the longitudinal direction, such lateral oscillations will have no effect thereon. If, however, the hand wheel 27 is turned in either direction, the yoke is revolved upon its axis, and. the switch oscillated in a longitudinal plane. The switch 22 is pivotally suspended at'the end of an arm 28 projecting laterally from the casing 24. The casing is revolved by means of the handwheel 29 through the medium of the reversing gear set 30. When the hand wheel 29 is moved in either direction', it rotates the shaft, which oscillates the switch 22 in the lateral direction. It will be readily understood that elevation and depression of the aeroplane do not have any effect on the switch 22, which being pivotally suspended remains in a vertical position, and is not oscillated ,latera-lly The purpose of the reversing gear set 30 is to, have the hand wheel 29 turned toward the right when it is desired to steer the aeroplane toward the right.

The switches themselves are very simple in construction, and each comprises a flat casing 31 adapted for pivotal suspension at its upper end. Within the casing a pendulum circuit maker 32 is provided, adapted to comiect the terminals 33 when oscillated in' one direction and the terminals 34 when oscillated in the opposite direction. In

order to prevent the circuit maker swinging too freely, or with very slight movements of the aeroplane, a small oil Iilled chamber 35 is provided on one side of the casing, con-' taining a pendulum 36 suitably connected 'with the pendulum 32, so that the movement of the pendulum 36 through the oil oflers suflicient resistance to the operation of the switch pendulum 32 to prevent. the

same contacting the terminals 33 or 34 on the occurrence of slight or momentary tiltings of the aeroplane. The circuit wires from the switches are preferably led out.

at the top' where the movement is least.

The electrical part of the device maybe arranged in a number of ways, of which only one is shown in Fig. 6. In this arrangement, 37 designates a source of electric energy from which current flows through the main 38. One terminal 33 and one terminal 34 in each switch is tapped on to the main by wires 39. Magnetically operable switches 40, 40, 41, '41 are also tapped on to this main 38, there being two switches for each pendulum switch, the switches 40, 40 pertaining to the switch 21 and the switches 41, 41 pertaining to the pendulum switch 22. The switches 40-41 and 34 of the pendulum switches are individually connected by wires 4.7 with the magnets 48, 48", 49 and 49 controlling the clutch levers 52 5 the operating magnets 50 of the switches 4O41 being in series between'the terminals and magnets 4849*. The magnets 4849= are each tapped on to a return main 51, leading through the main 46 to the source of energy. The mechanical disposition of the various magnets is very clearly illustrated in Fig. 6. The magnets 50 are arranged to open and close the switches 40.41. The magnets 4445 and 48-49 are arranged in pairs with common armatures 52, 52", 53 and 53 respectively between the magnets of each pair. The diagram shows the apparatus in condition of rest, that is, when the aeroplane is in a horizontal positiom It will be noted that the pendulums in the switches 21 and 22 are hanging free from all contacts, so that the terminals 33 and 34 are electrically disconnected throughout the system, although one of the terminals 33 and 34 in each switch are charged. The current flows through the main 38, through the switches 4041 and wires 43 to the magnets '4445, and from thence through the main 46 back to the source of energy. Thus, the magnets 4445 are energized and hold their armaverse tilting, one of the pendulum switches is brought into operation. In the same way,

if it is desired by the operator to move the aeroplane, one of the switches is oscillated by the means previously described. In either case, the electrical effect is exactly the same. As an example, supposing the pendulum switch 21 operates to connect the contacts 33, current then flows through the wire 39, connected terminals 33, through the wire 47- to themagnet48, and from thence through the wires 51 and 4'6 back to the source of energy. This energizes the magnet, so that it tends to draw the armature 52 away from the magnet 44. In order that this may be accomplished, the magnet 50 of the switch 40 is included in the circuit of the magnet 48, so that this magnet 50 lifts the switch 40 breaking the circuit of the magnet 44, and enabling the magnet 48 to draw up the armature 52. Obviously, either of the magnets 48, 48 may be in operation simultaneously with either of the magnets 49, 49, but the magnets 48, 48" and 49, 49 cannot be in operation simultaneously. The armatures 52 A30 5'3 inclusive are con- The operating power of the clutch is delivcred toa shaft 55 which rotates continuously and preferably at nnlform speed. This shaft is permanently connected by gears 56, a

57 with each of the four clutches, there being two clutches for each pulley. The pulleys and clutches are revolubly mounted on a fixed shaft 58. Each gear 57 is mounted on a boss 59 of the framework 54 in such a manner as to be held against longitudinal move-.

Inent. These bosses also support the shaft 58. A pair of sleeves 60 and 61 are mounted on the shaft 58, at their point of meeting lying within the pulley 16 which is hollow. One of the sleeves carries within the pulley a small gear 62, and-the other carries within the pulley a disk 63 having pivotally mounted thereon at regular intervals a series of planetary gears 64, which mesh with the gears 62 and with gear teeth 65 formed on the inner circun'iference of the pulley. Bevond the pulley, the sleeves 60 and 61 are shouldered, and are provided on the shoulders with end facing ratchet teeth 66. Outer sleeves 67 and 68 are revolubly and slidably mounted on the sleeves 60 and 61 respectively, and are at the same time slidably but irre-volubly mounted in the hubs of the gears 57. The ends of these outer sleeves adjacent the teeth 66 of the inner sleeve are provided with ratchet teeth 69, adapted to mesh with the teeth 66. The outer sleeves are grooved and carry rings 70, within which they revolve freely. These rings are trunnioned in the forked ends of levers 71 and 72, which are pivoted intermediate their ends, The opposite ends of the levers 71 and 72 from the forks are rigidly connected with the armatures 52 and 52 respectively. The

ends of the inner sleeves 60 and 61 remote from the pawl each carry end toothed collars 73 and 7-1 respectively, which are slidable but irrevoluble on the inner sleeves and revoluble but non-slidablein the outer sleeves.

It will thus be seen that these clutch collars will slide with the outer sleeves upon the inner sleeves, but will revolve with the inner sleeves. A complementary spring-pressed, end-toothed clutch ring 75 is slidably but irrevolubly mounted in each boss 59, for engagement with the clutch members 73 clutch teeth 66 and 69 out of engagement,

and the clutch members 73 and 71in mesh with the clutch members 7 5. It will "be remembered that the clutch members 7 3 and 7-1 are irrevolubly mounted on the sleeves and 61, which are positively connected to the pulley through the medium of the gears 62., 61 and and the disk 63. The pulley will therefore be held against revolution in either direction. lVhen the magnet 48 is energized, it draws the armature 52 and oscillates the clutch lever 71. throwing the revolving.

clutch sleeve 67 into mesh with the clutch sleeve 60 carrying the gear 62. At the. same time that engagement of the clutch members 60. 6 7 is effected, the clutch members '73. 75 are disengaged, thus unlocking the inner sleeve 60 and enabling the outer sleeve to rotate the same. The magnet r-l being unaffected, the clutch on the opposite side of the pulley is not shifted, so that the inner sleeve 61 remains locked against revolution, and consequently the disk 63 also remains stationary, so that the gears 64. have simple reversing action and drive the pulley 16 in the opposite direction from the gear 62. If the condition is reversed, that is. if the nmgnet 44 again draws up its armature and the magnet 4-1 releases its armature 52" to the m'ag net 48, the clutch members 60, 67 are disengaged and the clutch members 61,68 are engaged. Sin'ulltancously. the clutch members 73, 75 engage and look the inner gear 62 against revolution and the clutch members 7 r. 75 disengage and release the clutch member 61 for revolution with the member 68. The continuously rotating clutch member 63 drives the member 61 which is clutched to it, the disk 63 carrying the planetary gears 64. These; rotate around the fixed gear 62. and by reason of their engagement with theinternal teeth 65 of the pulley 16 revolvethe pulley in the same direction as the disk 63 As both the gears 57 drive in the same direction from the shaft, it will be noted that the pulley 16 is now turning in the reverse direction from that described in connection with the meshing of the clutch members 60 and 67. The same conditions prevail with regard to the pulley 17. v

From the foregoing description. the. operation of the device as a whole will-be readily understood, but for convenience may be summarized as follows :---Considering the acro plane to be traveling in a. horizontal plane, if theoperator wishes to turn to the right. he moves the hand wheel 29 to the right, with the result that the pendulum switch 22 is oscillated in a transveise plane. and closes the circuit of the magnet 49, which throws one of the clutches into connection with the pulley 17. Revolution of this pulley causes movement of the endless belt 18, and as will be readily seen from Fig. 1, inclines the right hand rudder 12 to cause depression of vthe right side of the machine, inclines the 1 plane to assume an inclined 01' canted position, which combined with the deflection of the stern rudder make turning very easy. When the hand wheel 29 1s returned to normal position, the various parts return to normal position and the machine is brought back to a horizontal plane; The sharpness of the turn is of course regulated by the length of time the hand wheel is held in a given position. A. sudden movement with rapid return to normal will in all probability have no effect on the apparatus, owing to the oil checked retarding pendulums 35.

The machine is raised or depressed in the same manner by operating the wheel 27, the

sharpness of the incline being regulated by the length of time which the wheel is held to its shifted position. If. while the machine is traveling in any position to which it 'is set, it becomes tilted in any direction by external forces, such as unforeseen air currents,

the pendulum switches will operate auton'iatically to rearran e the magnet circuits and thus automatically operate the rudders until the machine is brought back to the position determined by the set of the hand wheels 27 and 29.

From the foregoing, it will be seen that the operation of the steering and stabilizing mechanism is largely dependent on a. factor of time, that is, in manual steering, the amount of rudder deflection is dependent on the time during which the steering wheels are held out of normal position, and in the same way with the automatic stabilizing, the amount of deflection is dependent on the time during which the n'iaehinemaintains a position other than that for which it is set.

It therefore follows that when automatically stabilizing, the longer the machine remains in improper position, the greater becomes the'deflection of the rudders tending to correct the position. so that the correcting force increases with the time, and great displacements have automatically great corrections applied, the magnitude of the correction increasing as the error persists. In the case of steering, the invention presents considerable advantage over ordinary methods in that the magnitude of effect on the machine is not dependent on the distance which the steering wheel is turned, as in a. boat or automobile, but upon the time, so that only very slight movements of the wheels are necessary, thus enabling-corrections to be made more quickly and surely than-if the wheels had to be returned to normal through considerable distance. It also has the great advantage of preventing the rudders being moved too rapidly through great. angles.

Having thus described my invention, what I claim is 1. In a device of the class described, a pair of pendulum switches, oscillating in planes perpendicular to one another, ivotally suspended casings freely oscillata le in planes perpendicular to the plane of oscillation of the pendulum switches contained therein, and means for oscillating said casings in the planes of switch oscillation.

2. In a device of the class described, the combination with a forward elevation rudder, right and left elevation rudders, and a stern deflection rudder, of operating means for the forward rudder, and operating means for the right and left and stem rudders collectively, electro-lncclmnical controlling mechanism for said rudder operating means including pendulum switches and casings therefor, occupying a predetern'iined relation to an aeroplane, and means for altering suc-h relation.

3. In combination with a device according to claim 1, a driven shaft. a pair of drums, a pair of clutches for each drum driven in opposite directions by said shaft, and magnetic clutch operating means controlled by said pendulum switches.

4. A device according to claim 2, in which the operating means of the rudders includes a pair of revoluble drums, a driven shaft, and a pair of clutches for each drum operated by said shaft and reversing between each of said drums and one of its driving clutches.

5. A device according to claim 2, in which the electro-mechanical; controlling mechanism includes electro-magnets arranged in pairs, and clutch throwing levers arranged between the magnets of each pair.

6. A device according to claim 2 in which the operating means of the rudders includes a pair of revoluble drums, a driven shaft, :1 pairof clutches for each drum operated bysaid shaft and reversing between each of said drums and one of its driven clutches and an electro-mechanical driven mechanism including electro-magnets arranged in pairs and clutch throwing levers arranged between the magnets of each pair.

7. A device according to claim 2, in which the electro-mechanical controlling mechanism includes controlling levers for the rudder operating means, a pair of magnets for each lever arranged to pull in opposite directions, connections establishing a circuit through one magnet of each pair during normal position of the pendulum switches,

and pendulum switch operated means for breaking the circuit of said magnets and closing the circuit of the other magnets.

S. A device according to cla1m7, in which.

a the circuit breaking means of the first menmounted and simultaneously tioned magnets includes a magnetic switch in series with the second mentioned magnets and the pendulum switches.

9. A device according to claim 7, in which the circuit breaking means of the first men'- .tioned magnets includes a magnetic switch,

the circuit of which is established by oscillation of the pendulum switch.

10. A device according to claim 1, in

which the pendulum switches and the casings thereof are free to oscillate with the rocking of the vehicle on which they are in which the pendulum switches may be manually oscillated to set in operation vehicle tilting means.

11. In a device of the class described, a pair of gravity switches, a support therefor rotatable about two axes arranged at right angles, means for rotating both switches about their axes, said switches being arranged to oscillate'in perpendicnlarpla'nes, whereby only one switch will be affected by 0801113121011 of the support about either of the rotative axes.

12. In a device of the class described, the

' combination with a forward elevation rudder, right and left elevation rudders and a.

stern deflection rudder, of separate engine driven operating mechanisms for the forward rudder and for the right and left and stern rudders collectively, means normally holding said mechanisms inoperative, an electro-mechanical selective device arranged to throw inone of said holding means out of operation and to throw either of the operating mechanisms into action in either positive or reverse direction.

13. A device according to claim 12, in which the selective device includes a pair of pendulum switches oscillating in perpendicularplanes, and means for manually producing oscillation of said switches relatively to the body carrying them.

14. In a device of the class described, a pair of pendulum switches oscillating in planes perpendicular to one another, pivotally suspended casings freely oscillatable in lanes perpendicular to the lane of oscillatlon of the pendulum switc es contained therein, and means for oscillating said casmgs.

In witness whereof, I have hereunto set my hand. i

EVERETT KITTREDGE. 

